Looking at the lineup of G-Technology’s drives, it can be tough to distinguish between the many different but similar-looking options. G-Drive Pro with Thunderbolt ($700-$850) makes it pretty clear, though: it’s packing two full-speed Thunderbolt ports to take proper advantage of the fast transfer standard. Coming in 2TB and 4TB storage capacities, the drive is housed inside the trademark aluminum casing that looks great next to a Mac.…